taylor



W. TAYLOR.

DIVIDING HEAD.

APPLICAIIQN FILED AUG.9, I917.

F ZZ

W. TAYLOR.

DIVIDING HEAD.

APPLICATION men was. 1911.

1,323,658. Patented Dec. 2,1919.

2 SHEETS-SHEET 2.

Witnesses Inventor MM a WILLIAM TAYLOR, 9F LEIGESTER, ENGLAND.

:oivrnmennan.

Specification of Letters Patent.

Patented Dec. 2, 1919.

Application filed August 9, 1917. Serial No. 185,264.

To all whom it may concern: I

Be it known that I, VILLIAM TAYLOR, a subject of the King of England, residing at Leicester, in the county of Leicester, Eng land, have invented a certain new and useful Improved Dividing-Head, of which the following is a specification.

This invention relates to appliances for dividing circular or other objects, as in graduating, engraving, machining, and has for its object to provide improved means for chucking them and rotating them into and holding them in proper operative relat1on to the dividing, engraving or machining tools.

The invention embodies various improvements on the appliance for this purpose shown in the specification of prior British Letters Patent, granted to William Taylor and others. No. 6420 of 1894, wherein a work-holding plate or chuck, adapted to be rotated manually and'clamped in successive operative positions to effect the dividing, was provided with means for determining or indicating such positions, and with means for inclining the axis of rotation of the work-holder into any position from vertical to horizontal.

The subject of my present invention in its preferred form is illustrated by the accorm panying drawings, in which- Figure 1 is a plan view of the dividinghead with the axis of the work-holdersetvertically Fig. 2 is an end elevation showing in full lines the work-holder which is shown in plan in Fig. 1, and in dotted lines the work-holder inclined at an angle of45 to the vertical;

Fig. 3 is a side elevation of the apparatus viewed in the direction of the arrow placed in Fig. 1-;

Figs. 4. and 5 are respectively plan and front elevations of a catch-disk or indexplate for determining the angular positions to which the work-holder is rotatable about that axis which, in Fig. 1, is vertical, and a separate collar for adjustably securing the index-plate to the worksh older; and

Fig. 6 is a view of a detail B hereinafter particularly described. I Like reference-letters indicate like parts throughout the drawings.

Referring now to these drawings, a chuck or holder A for the work is adapted to rotate on a journal A 3), in a rigid supporting member B, in which it may be clamped by means of a screw B which is threaded into the member B and adapted to close, radially on to the journal A a part B (cross-hatched in Fig. 1 not to indicate that the part is in section, but merely to enable its position and extent to be more clearly apprehended) of the journal bearing, which part is for the purpose sufficiently detached (as shown in the separate View Fig. 6 which illustrates the part B removed from Fig. 1) from the member B to enable it to be thus closed. j j A convenient way of securing this partial detachment is to core through the member B a slot S, Figs. 1 and 6, so as to leave the part B in the form of a semicircular and pref erably flexible strap united with the sup porting member B at one endand adapted to be sprung inward at the other end so as to press, like one-half of a band-brake, on the journal A and also force it radially toward the fixed half of the hearing. The part B is preferably made flexible for the purpose of insuring that when it is forced inward against the journal A it shall not only force the journal against the fixed half of the'bearing but also shall close in on allsides of the arc of the journal which is embraced by it, thereby preventing all side shake andinsuring that the axis of the journal A at all times after the journal has been clamped shall in relation to the supporting member B and to the support of the pawl D (here inafter described) have one invariable position only. In order further to secure accuracy of position of the work-holder axis when its journal A is thus held by the strap B I may cut away a segment of the surface of the bearing, for example at 2 opposite thepoint ll where the strap puts its maximum pressure on the journal, so that the journal is held at such point and at points V, W, on either side of said segmental clearance, such points thus constituting at least a three-point bearing. This arrangement, beside having the merit of simplicity, renders the accuracy of dividing independ ent of wear or looseness of the journal.

The supporting member B is carried adjustably by a base F which with the means for retaining and adjusting the supporting member uponit hereinafter described are not of the present invention) so to vary,

drical surface F on the base F, being guided in its movement about the axis g (F 3 1.) and HQVQDiGCl from moving alon a 1 h a that axls b a ton ue F which fits see Fig. 1) in the open or stem partof the T slot B The cylindrical surface of the part B is held against the surface F on the base by a bolt F with head F adapted to engage within the head or cross-portion of the T slot B and caused to draw the part B radially into engagement with the surface F by means which may comprise a thrust piece F (Fig. 2) and a screw F which is threaded into the part F and may be operated by a removable key F In order to prevent the contiguous parteylindrical surfaces of the parts B and F from becoming sufficiently separated to admit chips or dirt when the screw F is slackened, a second thrust-piece F is provided, and an adjusting-screw F therefor. This second thrust-piece. while it is adapted to: prevent the said surfaces from being so separated, is so adjusted as to leave them free to slide relatively, in a circular are 7 when the screw F is'slackened.

It will be seen from Fig. 2 that there are two flats F F at an angle on the stem of the bolt F it is upon the fiat F that the thrust-piece F bears and upoii' the flat F that the second thrust-piece F bears, so

*that the thrust-pieces may exert each its desired degree of pressure upon the bolt F The part 13 and the base F may be graduated as shown to indicate the angular inclination of the workholder on the base F, and adjustable stops may be provided to hunt thls motion of the member B on the base F, for example, to positions in which the work-holder axis is respectively parallel to, and at right-angles to. the undersideiof' the base F. Such an adjustable stop or stops may be formed by one or more cylindrical reds B Each rod 13* is parallel with'the axis of rotation of the member B and the ends of each rod fit in holes in the member B, so that the middle of each rod slot and adapted to engage the stops P) may be one or more projections forming abntments F and the center part of each rod B which engages a rorrespoiuling abutment F is'formed eccentrically (as sliOWH in Figs. 2 and 3) so that by turning the rod 13*, as by means of the screwdriver slot B" (Fig. 3) in its end, the circumference of the center part of each rod, which part is theeffective portion of the stop, can be moved toward and away from the contiguous abutment F Thus the position of rest of the abutment against the stop can receive minute adjustment whereby the position of rotation of the member B on the base- F may be finally precisely adjusted. Set-screws B are used to clamp the rods B after the latter are adjusted.

The work-holder A may be in the form shown, 2'. e. a face-plate having radial T slots or other equivalent means of securing the work thereto, and it may have therein a central hole A in which a plug may be placed for centering the work upon, or through which a bolt may bepassed for securing work to the work-holder. Or the work-holder may have the form of a projecting spindle having cylindrical or conical surfaces, or other convenient means such as are well-known, forcentering'and securing the work, but any such device is herein referred to as a work-holderf Such a workholder is conveniently provided nit-ha scale of divisions such as A (Figs. 2 and 3) around its periphery, and a ;reader B (Fig. 1) against which such graduations ing inB, and adjusted to be free of end;

shake by means of a nut A (Fig. 3) threaded on ma pro ect ng end of the ournal A To insure that the nut A" shall be secure in its position thereon it can be slit radially in one place, and the screw be made a tight fit so that the nut will beheld in place by its elastic pressure on the screw. r

In order to provide means for determining, apart from the scale of gra'duations A the operative position or positions of rotation of the work-holder A about its axis, its central hub or journal A has a concentric eXtensionA (Fig. 3) on whose cylindrical exterior may be fitted interchangeably so as to abut against the face of the nut A1 or an equivalent shoulder any number of catch' disks or index plates C (Figs. 4: and 5) having suitable holes, or

preferably notches for example C 1in their peripheries, and adapted to engage aspring actuated pawl D (Figs. 1 and 3) pivoted on a post B fiXed on the nieznberB. The purpose of the pawliids to constitute a device against the tipofwhich the notches of the index plates (lanav be abutted togive the work-holder A definite angular posi-- tion in'relation to the bearing in which its journal A is supported 1 The index, plates C are centered ting them closely on the hub A, and an index plate can be held adjust-ably thereon or secured against rotation by mean of a separate collar E rotatable and clarnpable on the hub A by a screw E which closes a slit through one side of the collar. The index plate C h as in it two holes C C which engage the conical ends of pins E and it projecting from one face of the collar E. The holes and pins are at one common radial distance from the center of the index alate and the holesare preferably placed as shown in -.lon a straight line through the centerof the plate, 2'. 6. 180 apart. The pin are, however, so arranged that when partially entered they engage the holes :at one common side which is toward the slit E of the collar E, as shown in Fig. and offectually hold the index plate'G against all rotation in spite of normal imperfection in the size or position of the pins or holes C (1 if, in the entry of one conical pin into its hole, the coned end of the other is not in contact with the wall of the corresponding hole the pin that has first found a bearing in its hole will, upon the collar being moved toward the index plate, slightly shift the index plate around on the hub until the other hole comes into contact with the other pin, and when the screw E is then tightened to secure the collar it tends to move the pins E, more closely into contact with their respective sides of the holes. Thus the inllGX plate is held finally by a three-point bearing of which one point is at the side of the hub remote from the slit in the collar and the other two are at that side of the coned ends of the pins E E which is remote from the first point.

The arrangement permits of securing the index plate on the hub A either way around, 2'. c. with either face outward, so that it operates either right or left-handedly.

The pawl D may be placed on thepost B either way around so as to suit either the right or left-handed position of the index plate C, and in either such positionis held against withdrawal from the post B and normally urged to engage the index plate, by means of a spring D (Fig. 1) which as hown held by the crew D in the bottom of an open groove machined in one side of the tail end I)? of the pawl, the free end of the spring, which is forced or sprung outward from the said groove against its own resistance, engaging in one or other of two transverse open slots or flats B and B symmetrically formed transversely in opposite sides of the post B The spring is so disposed as to engage either of the flats B or B at an angle a at that end of the flat which is more ren'iote from the screw D than is the opposite end, and the free end of the spring ispressed against that end of the flat by the tension of the spring for the free end aforesaid is made to react always &

toward the post. When the free end of the spring is acting on what is the left hand end in Fig. i of the flat B the reaction at D of the other end of the spring can bring about a relative motion between the two ends of tl spring which is in such a direction as to urge the pawl D around the post negatively, or in a counter clockwise direction; and as at such time the pawl D is in the dot ed line position its claw will be pressed toward the index plate.

Nith the pawl reversed on the post B which may be accomplished by slipping it off the end of the post and turning it over so tl at it assumes the position indicated in dot and dash or chain lines, Fig. 1, the spring will act at an angle and on what is the left hand end in Fig. l of the upper slot B and the pawl D will consequently be urged around the post by the spring positively toward the index plate.

By turning or rotating the pawl partially around the post until the free end of the spring I 1 bears on the oylindric portion of the periphery of said post the tendency of the spring to turn the pawl is neutralized because for the spring to effective to perform any work. 0. g. to turn the pawl, there must be a relative displacement of opposite ends of the spring one in relation to the other, and this is not possible so long as the spring rests on the cylindric part around the axis of which alone the pawl is movable. lVhen the spring is thus resting on the cylindrie part of the post t is claw of the pawl I) is clear of the teeth on the index plate C and will be kept so until the spring is once more made to rest on one or other of the flats B B it will be seen that the spring D is so placed to draw the pawl against that side of the post B to which the pawl is urged by engagement with the index plate, so that in this way back-lash between the pawl. and the post has no effect on the accuracy of dividing.

Two edges F and F 1) of the base F- are machined square to one another in plan, the latter being parallel to the axis of the part-cylinder B in order to facilitate setting the appliance squarely on any machine to which the apparatus may c hel d by dogs bearing upon the flanges of the base.

What I claini as my invention and desire to secure by Letters Patent is 1. A dividing head comprising a rotary work holder having a cylindrical journal connected thereto, a support forming a re ceiver for the journal and arranged to form a bearing therefor, a portion oi said support forming a seat for the journal to accurately position the axis of the journal during the rotation thereof, said support also having a flexlble segment arranged to pass around a portionof the ournal, andnieans for se- &

curing said flexible segment in position to clamp the work holder and force it to its seat, substantially as described. 7 2. A d1v1d1ng head comprising a rotary' work holder having a cylindrical journal connected thereto, a support forming a receiver for the journal and arranged to form a bearing therefor, said support having two separated bearing surfaces forming seats for the journal to accurately position the axis of the journal during the rotation thereof, together with a flexible segment connected at one end to the. support and passing around a portion of the journal, and means for securing said flexible segment in position to clamp the work holder, substantially as de scribed. v

3. A dividing head comprising a rotary work holder having a cylindrical journal connected thereto, a support forming a re ceiver for the journal and arranged to form a bearing therefor, a portion of said support forming a seat for the journal to accurately position the axis of the journal during the rotation thereof, said support also having a flexible segment arranged to pass around a portion of the journal, means for securing said flexible segment in position to clamp the work holder, a pawl support connected to the work holder support, and a pawl pivoted thereto in operative engagement with the work holder, substantially as described.

clamp the work holder, a pawl support con nected to the work holder support, and a pawl pivoted thereto in operative engagement with the work holder, substantially as described.

5. The combination of a dividing head work holder and a removable annular index plate on the work holder, of a removable clamp-collar on the work holder, conical ended pins connecting the index plate and the clamp collar arranged to position the index plate'with relation to the clamp-collar and force the index plate against a bearing on the work holder, substantially as described.

6. A dividing head having a rotarywork -holder, an index plate thereon, a fixed cylindrical post having an open slot in its side, a pawl rotatably mounted on the post and adapted to engage the index plate, and a drical post having an open slot in its side,

a pawl rotatably mounted on the post and adapted to engage .the index plate, and a spring on the pawl adapted to engage one end of the slot to urge the pawl about an axis on the post and. to engage thesides of the slot to position the pawl longitudinally on the post, the end of the slot having'a.

cylindrical surface concentric with the post, arranged to be engaged by the spring when the pawl is idle, substantially as described.

8. A dividing head comprising a rotary work holder and an index plate thereon, a fixed cylindrical post having an open trans verse slot in its side, a pawl rotatably mounted on. the post and adapted to engage the index plate, and a spring on the pawl adapted to engage one surface .in the slot to urge the pawl about the axis thereof, said spring also being arranged to engage the sides of the slot tov position the pawl longitudinally on the post, said" spring being so placed upon the pawl as to draw the pawl against that side of the-post against which the pawl is urged by the action of theteeth of the index plate, substantially as described. 9. A dividing head comprising a rotary work holder and an index plate thereon, a

fixed cylindrical post having an open transverse slot in its side, a pawl rotatably mounted on the post and adapted to engage the index plate and a spring on the pawl Y adapted to engage one surface in'the slot to urge the pawl about the axis thereof, said spring also being arranged to engage the 7 sides of the slot 'to position the pawl longitudinally on the post, the-end of the slot having a cylindrical surface concentric with the post which is engaged by the spring when the pawl is idle, said spring being so placed upon the pawl as tofdraw the pawl against that sideof the post'against which the pawl is urged by the action of the teeth of the index plate, substantially as described. 7

10. A dividing head comprising arotary work holder and an index plate thereon, a fixed cylindrical post having two transverse slots in its side, areversible pawlon said post adapted to engage the index plate, and

- a spring on the pawl adapted to engage one end of the wallof one slot, to rotate the pawl about theaxis thereof towardthe index plate, the spring also being arranged to engage both side walls of said slototo retain the pawl inposition, the other slot being also adapted to be engaged by the spring when the pawl is reversed, the spring being adapted to urge the pawl 1n the reverse direction positions to which itnioves relatively to the bolt, and two screw-adjusted thrust rodsin sockets in the base and engaged with the shank of the bolt at diiierent places therein, substantially as described.

12. In a dividing head the combination of a rotary work holder, a supporting member therefor having a part cylindrical surface, abase havinga counterpart part-cylindrical surface and adapted to carry the sup porting member adjustably, a tongue and groove connection between the supporting member and base and means to limit such adjustable movement comprising an adjustable stop within the groove adapted to engage an abutment on the tongue and constituted by a cylindrical rod set in and projecting from a hole in the groove, and means for rotating, and means for clamping it in said hole, the portion of the stop which lies within the groove being eccentric for the purpose described.

13. In a dividing head the combination with a rotary work holder, a cylindric j ournal fixed upon the holder, a support having a receiver for the journal, the said holder and journal being adjustable radially as a unit relatively to their support, which receiver as to one part thereof is a rigid concavo-eylindric seat to seat the journal accurately and thereby determine with accuracy the position that the axis of the journal shall occupy during the rotation of the journal in said part and as to another part is a flexible segment which is fixed at one end to said receiver and bears on the side of the journal that is out or" the rigid seat, the said flexible segment serving to press the journal radially into the seat of the receiver.

14. In a dividing head the combination with a rotary work holder, a cylindric j ournal fixed upon the holder, a support having receiver for the journal, the said holder and journal being adjustable radially as a unit relatively to their support,'which receiver as to one part thereof is constructed with a ri id concavo-cylindric seatconsisting of two separated bearing projections to seat the journal accurately and thereby determine with accuracy the position that the axis of the journal shall occupy during the rotation of the journal in said part and as to another part is a flexible segment which is fixed by one end to said receiver and bears on the side of the journal that is out of the rigid seat, the said flexible segment serving to press upon that side of the journal which is remote from the two separated bearing surfaces aforesaid so as to press the journal radiallyinto the seat of the receiver.

15. In a dividing head the combination with a rotary work holder, a cylindric journal fixed upon a holder, a support having a receiver for the journal, the said holder and journal being adjustable radially as a unit relatively to their support, which receiver is a rigid concavo-cylindric seat as to one part thereof to seat the journal accurately and thereby determine with accuracy the position that the axis of the ournal shall occupy during the rotation oithe journal in said part and is as to another part as a flexible segment which is fixed at one end to thereceiver and bears on the side of the journal that is out of the rigid sea" and serves to press the journal radially into the seat of the receiver, a pawl in operative engagement with the work holder, and a pawl support fixed on the aforesaid receiver.

16. In a dividing head the combination with a rotary work holder, a cylindricjournal fixed upon the holder, a support having a receiver for the holder, the said holder and journal being adjustable radially as a unit relatively to their support, which receiver as to one part thereof is a rigid concavocylindric seat consisting of two separated bearing projections to seat the journal accuately and thereby determine with accuracy the position that the axis of the journal shall occupy during the rotation of the journal in said part and as to another part is a flexible segment with one end fixed to said receiver, the said flexible segment serving to press upon that side of the journal which is remote from the two separated bearing projections aforesaid so as to press the journal radially into the seat of the receiver, a pawl-in operative engagement with the work holder, and a pawl support fixed on the aforesaid receiver.

17. In a dividing head the combination with the work holder of a removable annular index plate on the work holder, a removable clamp collar on the work holder, wedge devices comprising two cone ended pins and constituting an operative connection between the index plate and clamp collar whereby the index plate is caused to take a three point shakeless bearing whereof the three points are respectively on one side of the cone of each pin and on the work holder at one side of the axis of the latter.

18. In a dividing head comprising a rotary Work holder and an index plate thereon, the combination of a fixed cylindrical post having an open transverse slot in its side, a pawl rotatable on the post and adapted to engage the index plate, and a spring on the pawl adapted to engage one end of the slot so as to urge the pawl slot so as to position the pawl longitudinally onthe post, the said post having at the end of the slot a cylindrical surface concentric with the post, whereon the spring may be brought to bear when the pawl is to be idle. V

20. In a dividing head comprising a rotary work holder and an index plate thereon, the combination of a fixed cylin drical post having an open transverse slot in its side, a pawl rotatable on the post and adapted to engage the index plate, and a spring on the pawl adapted to engage one end of the slot so as to urge the pawl rotationally On the post and to engage the sides of the slot so as to position the pawl longitudinally on the post, and the said spring being so placed upon the pawl as to draw the pawl against that side of the post to which the pawl is also urged by the action upon it of the teeth of the index plate.

21. In a dividing head comprising a rotary work holder and an index plate thereon, the combination of a fixed cylindrical post having an open transierse slot in its side, a pawl rotatable .on the post and adapted to engage the index plate, and a spring on the pawl adapted to engage one end of the slot soas to urge the pawl rotatlonally on the post and to engage the sides of the slot so as -to -position the pawl longi-' tudinally on the post, the said post having at the end of the slot a cylindrical surface concentric with the post, whereon the spring may be brought to bear when the pawl is to be idle, and the said spring being so placed upon the pawl as to draw the pawl against that side of the post to which the pawl is also urged by the action upon it oi"? the teeth of the index plate.

In testimony whereof I have signed .my name to this specification in the presence of two subscribing witnesses.

WILLIAM TAYLOR.

lVitnesses 1 THOMAS Enemy Henson, ELsIE M. BENT. 

